In the future, advances in our understanding of the human microbiome will make microbiota transplantation (MT) - transplantation of bacteria from a healthy individual to a patient recipient to cure or manage a health condition - increasingly common. At present, there is much interest and evidence-based support for one type of MT, fecal microbiota transplantation (FMT), a procedure that is emerging as an effective treatment for Clostridium difficile infection and may also be effective in treating other conditions. FMT is raising new legal and regulatory questions for the Food and Drug Administration (FDA). Although FMT is the focus of much attention, other emerging MT options include vaginal, skin, oral, and anterior nares transplantations. Use of these other MT options is still in its infancy an there has been little, if any, discussion in the literature as to their appropriate regulation. The proposed project will convene a multi-disciplinary Working Group to evaluate alternative regulatory options for MT (with FMT as a primary focus) and consider which regulatory approach or approaches would make MT available in a way that meets specific criteria for regulatory effectiveness. The invited Working Group will comprise 20-25 expert stakeholders, including scientists, clinicians, patients, professional associations, bioethicists, government regulators, academics, lawyers, and biotechnology industry representatives. The Working Group will study how FMT is currently regulated and how substances and procedures similar or analogous to MT are regulated (e.g., biological products, blood and blood products, and transplantation of human organs and tissues) to determine if some or all of these regulatory options might be appropriate for some or all forms of MT. The Working Group will analyze the degree to which each existing regulatory scheme meets a set of criteria that determines whether the regulatory framework is appropriate for FMT and other forms of MT. Specifically, each regulatory framework will be analyzed to determine if - in relation to some or all forms of MT - it would: 1) ensure the safety of the substance/procedure; 2) ensure the effectiveness of the substance/procedure; 3) provide reliable information to recipients about the safety and effectiveness of the substance/procedure; 4) ensure that patients who need them have appropriate access to these substances/procedures; 5) ensure that the regulations do not unnecessarily discourage research on MT; and 6) support public health objectives relating to MT, including its potential to mitigate hospital acquired- infections and to discourage unsafe home use of MT. At the conclusion of the project, the Working Group will set forth a series of recommendations regarding how MT should be regulated going forward and these recommendations will be published in a paper or series of papers.